Commit 47d9c7cc authored by Amir Goldstein's avatar Amir Goldstein Committed by Jan Kara
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fsnotify: generalize iteration of marks by object type 



Make some code that handles marks of object types inode and vfsmount
generic, so it can handle other object types.

Introduce fsnotify_foreach_obj_type macro to iterate marks by object type
and fsnotify_iter_{should|set}_report_type macros to set/test report_mask.

This is going to be used for adding mark of another object type
(super block mark).

Signed-off-by: default avatarAmir Goldstein <amir73il@gmail.com>
Signed-off-by: default avatarJan Kara <jack@suse.cz>
parent d9a6f30b

fs/notify/fsnotify.c

+28 −24
Original line number Diff line number Diff line
@@ -269,25 +269,29 @@ static struct fsnotify_mark *fsnotify_next_mark(struct fsnotify_mark *mark) 
static unsigned int fsnotify_iter_select_report_types(

		struct fsnotify_iter_info *iter_info)

{

	struct fsnotify_mark *inode_mark = iter_info->inode_mark;

	struct fsnotify_mark *vfsmount_mark = iter_info->vfsmount_mark;

	int cmp;

	struct fsnotify_group *max_prio_group = NULL;

	struct fsnotify_mark *mark;

	int type;



	/* Choose max prio group among groups of all queue heads */

	fsnotify_foreach_obj_type(type) {

		mark = iter_info->marks[type];

		if (mark &&

		    fsnotify_compare_groups(max_prio_group, mark->group) > 0)

			max_prio_group = mark->group;

	}



	if (!inode_mark && !vfsmount_mark)

	if (!max_prio_group)

		return 0;



	if (inode_mark && vfsmount_mark) {

		cmp = fsnotify_compare_groups(inode_mark->group,

					      vfsmount_mark->group);

	} else {

		cmp = inode_mark ? -1 : 1;

	}



	/* Set the report mask for marks from same group as max prio group */

	iter_info->report_mask = 0;

	if (cmp <= 0)

		iter_info->report_mask |= FSNOTIFY_OBJ_TYPE_INODE_FL;

	if (cmp >= 0)

		iter_info->report_mask |= FSNOTIFY_OBJ_TYPE_VFSMOUNT_FL;

	fsnotify_foreach_obj_type(type) {

		mark = iter_info->marks[type];

		if (mark &&

		    fsnotify_compare_groups(max_prio_group, mark->group) == 0)

			fsnotify_iter_set_report_type(iter_info, type);

	}



	return iter_info->report_mask;

}
@@ -298,13 +302,13 @@ static unsigned int fsnotify_iter_select_report_types( 
 */

static void fsnotify_iter_next(struct fsnotify_iter_info *iter_info)

{

	if (iter_info->report_mask & FSNOTIFY_OBJ_TYPE_INODE_FL)

		iter_info->inode_mark =

			fsnotify_next_mark(iter_info->inode_mark);

	int type;



	if (iter_info->report_mask & FSNOTIFY_OBJ_TYPE_VFSMOUNT_FL)

		iter_info->vfsmount_mark =

			fsnotify_next_mark(iter_info->vfsmount_mark);

	fsnotify_foreach_obj_type(type) {

		if (fsnotify_iter_should_report_type(iter_info, type))

			iter_info->marks[type] =

				fsnotify_next_mark(iter_info->marks[type]);

	}

}



/*
@@ -351,15 +355,15 @@ int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is, 


	if ((mask & FS_MODIFY) ||

	    (test_mask & to_tell->i_fsnotify_mask)) {

		iter_info.inode_mark =

		iter_info.marks[FSNOTIFY_OBJ_TYPE_INODE] =

			fsnotify_first_mark(&to_tell->i_fsnotify_marks);

	}



	if (mnt && ((mask & FS_MODIFY) ||

		    (test_mask & mnt->mnt_fsnotify_mask))) {

		iter_info.inode_mark =

		iter_info.marks[FSNOTIFY_OBJ_TYPE_INODE] =

			fsnotify_first_mark(&to_tell->i_fsnotify_marks);

		iter_info.vfsmount_mark =

		iter_info.marks[FSNOTIFY_OBJ_TYPE_VFSMOUNT] =

			fsnotify_first_mark(&mnt->mnt_fsnotify_marks);

	}

fs/notify/inotify/inotify_user.c

+4 −4
Original line number Diff line number Diff line
@@ -485,10 +485,10 @@ void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark, 
				    struct fsnotify_group *group)

{

	struct inotify_inode_mark *i_mark;

	struct fsnotify_iter_info iter_info = {

		.inode_mark = fsn_mark,

		.report_mask = FSNOTIFY_OBJ_TYPE_INODE_FL,

	};

	struct fsnotify_iter_info iter_info = { };



	fsnotify_iter_set_report_type_mark(&iter_info, FSNOTIFY_OBJ_TYPE_INODE,

					   fsn_mark);



	/* Queue ignore event for the watch */

	inotify_handle_event(group, NULL, FS_IN_IGNORED, NULL,

fs/notify/mark.c

+15 −8
Original line number Diff line number Diff line
@@ -294,12 +294,12 @@ static void fsnotify_put_mark_wake(struct fsnotify_mark *mark) 


bool fsnotify_prepare_user_wait(struct fsnotify_iter_info *iter_info)

{

	int type;



	fsnotify_foreach_obj_type(type) {

		/* This can fail if mark is being removed */

	if (!fsnotify_get_mark_safe(iter_info->inode_mark))

		return false;

	if (!fsnotify_get_mark_safe(iter_info->vfsmount_mark)) {

		fsnotify_put_mark_wake(iter_info->inode_mark);

		return false;

		if (!fsnotify_get_mark_safe(iter_info->marks[type]))

			goto fail;

	}



	/*
@@ -310,13 +310,20 @@ bool fsnotify_prepare_user_wait(struct fsnotify_iter_info *iter_info) 
	srcu_read_unlock(&fsnotify_mark_srcu, iter_info->srcu_idx);



	return true;



fail:

	for (type--; type >= 0; type--)

		fsnotify_put_mark_wake(iter_info->marks[type]);

	return false;

}



void fsnotify_finish_user_wait(struct fsnotify_iter_info *iter_info)

{

	int type;



	iter_info->srcu_idx = srcu_read_lock(&fsnotify_mark_srcu);

	fsnotify_put_mark_wake(iter_info->inode_mark);

	fsnotify_put_mark_wake(iter_info->vfsmount_mark);

	fsnotify_foreach_obj_type(type)

		fsnotify_put_mark_wake(iter_info->marks[type]);

}



/*

include/linux/fsnotify_backend.h

+25 −3
Original line number Diff line number Diff line
@@ -211,23 +211,45 @@ enum fsnotify_obj_type { 
#define FSNOTIFY_OBJ_ALL_TYPES_MASK	((1U << FSNOTIFY_OBJ_TYPE_COUNT) - 1)



struct fsnotify_iter_info {

	struct fsnotify_mark *inode_mark;

	struct fsnotify_mark *vfsmount_mark;

	struct fsnotify_mark *marks[FSNOTIFY_OBJ_TYPE_COUNT];

	unsigned int report_mask;

	int srcu_idx;

};



static inline bool fsnotify_iter_should_report_type(

		struct fsnotify_iter_info *iter_info, int type)

{

	return (iter_info->report_mask & (1U << type));

}



static inline void fsnotify_iter_set_report_type(

		struct fsnotify_iter_info *iter_info, int type)

{

	iter_info->report_mask |= (1U << type);

}



static inline void fsnotify_iter_set_report_type_mark(

		struct fsnotify_iter_info *iter_info, int type,

		struct fsnotify_mark *mark)

{

	iter_info->marks[type] = mark;

	iter_info->report_mask |= (1U << type);

}



#define FSNOTIFY_ITER_FUNCS(name, NAME) \

static inline struct fsnotify_mark *fsnotify_iter_##name##_mark( \

		struct fsnotify_iter_info *iter_info) \

{ \

	return (iter_info->report_mask & FSNOTIFY_OBJ_TYPE_##NAME##_FL) ? \

		iter_info->name##_mark : NULL; \

		iter_info->marks[FSNOTIFY_OBJ_TYPE_##NAME] : NULL; \

}



FSNOTIFY_ITER_FUNCS(inode, INODE)

FSNOTIFY_ITER_FUNCS(vfsmount, VFSMOUNT)



#define fsnotify_foreach_obj_type(type) \

	for (type = 0; type < FSNOTIFY_OBJ_TYPE_COUNT; type++)



/*

 * Inode / vfsmount point to this structure which tracks all marks attached to

 * the inode / vfsmount. The reference to inode / vfsmount is held by this

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